Tiffany Hills Animal Hospital

Posts tagged “immune system

What is All the Confusion with Vaccines? Part Two

The pet’s immune system protects from diseases. The immune system is a very complicated system divided into two parts, cell mediated and humoral (blood) mediated. Each of these parts has many components working to protect our pets from getting diseases. There are parts of the immune system that react indiscriminately to a threat. Look at any abscess, the pus cells (white blood cells) are fighting the infection no matter what the bacteria causing it. And there are segments that are very specific to the threat. Vaccinate a pet against distemper and that segment of the immune system is primed for distemper only.

The pathogen (bacteria, parasite, or virus) can be fought at the exposure site, in the blood, and/or in a lymph node. Basically, the pathogen enters the host, certain cells release chemicals as a call to arms. The pathogen is tagged by either another cell and/or chemical (antibody) and presented for destruction or neutralization by another cell. Then certain times another cell is encoded with memory of this pathogen. Most memory is finite and some is lifetime.

A vaccine is an altered disease pathogen. A vaccine should not produce the illness if the pathogen has been altered correctly. So we get the benefit of protection without having to go through the disease.

Out of all this complicated immune system and all the cells interacting with each other, the only thing that can be measured are the antibodies in the blood. That measurement is called titer. A titer is a measurement for a specific antibody and specific disease. There is no other test that can measure all the cellular activity or the chemicals released to communicate between the cells, just the antibodies in the blood. There even is no test for antibodies that line mucous membranes like the nose, mouth, or gut. Therefore, most of the immune system that protects us is “invisible” to testing.

So what does titer testing tell us? That there are antibodies produced from some sort of exposure (natural or vaccine). As many immunologist and internist say “the numbers are meaningless.” There are no standards for what is protective and what is not. Vaccine companies do not use titers for testing their product, they use exposures. The vaccinated animal is exposed to the disease. Results are a simple “ got sick” or “did not get sick.”

So now what do we do?
​1. Testing for several diseases in more costly than vaccinations.
​2. As of right now, testing takes several days for the results.
​3. No standard for interpretation of the titers.
​4. Some diseases, the protection is local antibodies (IgA) which can’t be tested. Any intranasal vaccine stimulates the local immunity.

Pet owners want titers instead of vaccines. What is the best thing for the pet?
​1. A lot depends on the pet’s family medical history. Or, breed predilections if the family medical history is unknown.
2. Risk assessment and environment is important to consider.
3. Three year vaccines are safer.
4. I have witnessed overdue pets getting sick.
5. Puppies and kittens need a series of vaccinations (see Part Three).
6. If pet owners want titers, then they are falsely assuming their pet will be protected based solely on titers.

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What is All the Confusion with Vaccines? Part Three

Puppies and kittens have unique set of circumstances that needs to be addressed so ultimately they will be protected. Puppies and kittens are born with a pure untainted immune system, no antibodies or memory cells. If they are exposed to disease, they get sick. So in order to protect newborns, an amazing phenomenon happens. The mother’s milk contains all of her antibodies. This first milk is called colostrum. The first 24hrs of nursing, the infant’s gut will absorb these large protein molecules directly into their blood stream. After 24hrs, the milk is digested. So, it is very important for newborn puppies and kittens to nurse the first 24hrs. It is also important the mother be current on her vaccines before breeding.

So what does this maternal immunity do? It protects the puppies and kitten from all the diseases the mother is protected against. But there are two catches, it is temporary and it cannot tell the difference between vaccine pathogen and the disease pathogen. These two “catches” dictates the puppy’s and kitten’s vaccine schedules.

Statistically, 95-99% of the 6 week old puppies and kittens that nursed are protected by the maternal antibodies. At 8 weeks of age about 80-90% of the puppies and kittens are still protected by the maternal antibodies. At 12 weeks of age 10% of the puppies and kittens are protected. And by 16 weeks of age the maternal antibodies are gone. Any attempt to vaccinate puppies less than 12 weeks of age has a chance the vaccine will be neutralized by the maternal antibodies and the puppy and kitten will get no benefit.

An immune system needs stimulation from at least two injections. The first vaccine starts the process and then 3-4 weeks later the second stimulates the memory response. Then each booster rekindles the memory cells.

So how do we vaccinate puppies and kittens? The vaccine schedule is made by using the statistics of the maternal antibodies. So any vaccine given 6 weeks or earlier did not hurt the puppy or kitten but did not help the puppy or kitten either. Most veterinarians start the vaccines at 8 weeks of age, give boosters at 12 weeks of age, and finish the series at 16 weeks of age. This is the least amount of shots that ultimately stimulates the puppy’s and kitten’s immune system for a full year. Whether the puppy gets a 100 vaccines or 3 leading up to 16 weeks of age, the outcome is still the same.

Boosters are given 1 year later. Evaluating the pet’s environment and exposure dictates what vaccines to give. This is also another good time to use 3 yrs vaccines.

Rabies vaccines are handled a little different. Each municipality dictates the vaccine schedule for puppies and kittens. Rabies vaccine can be given as young as 12 weeks of age. Dogs and cats are then revaccinated 1 year later. Again, the municipality will dictate whether 1 or 3 year vaccines will be recognized. Only licensed veterinarians can give rabies vaccine to be valid.